<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<body>
    <form action="http://192.168.40.90:80/main" target="myIframe" method="POST" id="myForm">
        <input type="text" name="companyName" type="hidden" value="1111" id="">
        <input type="text" name="username" type="hidden" value="2222" id="">
        <input type="button" onclick="formSubmit()" value="Submit">
    </form>
    <iframe id="myIframe" name="myIframe" width="100%" height="1000px" allowTransparency="true" align="center" scrolling="no" frameborder="0" border="0" hspace="0" vspace="0" marginheight="0" marginwidth="0"></iframe>
    <script>
        function formSubmit() {
            document.getElementById("myForm").submit()
        }
    </script>
</body>
</html>